The invention relates to a fastening unit for connecting a device to two spaced-apart headrest rods of a vehicle seat, and to a device of this type for suspending objects on a vehicle seat part, such as a backrest, headrest or a headrest mount of a vehicle seat.
A fastening unit has been described by the applicant in WO 2008 131 944 A1, to which reference is made. The described fastening unit comprises a receiving bushing which can be fastened to the headrest rods of a vehicle seat by means of fastening elements, and a plug element which is plugged into the receiving bushing and is secured by a releasable locking mechanism. The plug element is part of various modules which can thus be mounted exchangeably on the vehicle seat and can be removed and interchanged.
In order to attach the fastening unit to the headrest rods, a first and a second fastening element are placed onto two opposite sides of the headrest rods and are clamped against the headrest rods by means of a screw connection.
This results in a stable connection, thus enabling even relatively large devices, for example a folding table or a clothes-hanging device, to be stably fastened to the vehicle seat.
The headrests fitted on the vehicle seats for the driver and passenger can be adjusted in height manually or electrically and can thus be adapted individually to different user heights. This is required for improving the seat comfort, but in particular for optimum supporting of the head during rear-end collisions.
However, by means of a fastening unit mounted on the headrest rods, the height adjustability of the headrest may be restricted such that the fastening unit has to be removed from the headrest rods in order to set certain positions of the headrest, which has an adverse effect on the operating convenience of adjusting the headrest.
Fastening units which permit height adjustment of the headrest to which they are fastened are also known from practice. Generally, adapter pieces, for example in the form of short tubes, in which the headrest rods can move axially and to which the fastening units can be secured, are attached to the headrest rods or to the guides thereof in the backrest of the vehicle seat.
However, these solutions are tailored to certain diameters and spacings of the headrest rods. In addition, the mounting on the vehicle seat is associated with a considerable outlay and can only be carried out by a person skilled in the art. The headrests often for this purpose have to be completely pulled out of the mounts thereof in the backrest, which is frequently no longer possible at all in the case of modern headrests.
If the devices or fastening units are removed, the adapter pieces remaining on the headrest rods or the guides thereof frequently pose a considerable risk of injury to the passengers in the rear seats, in particular in the case of accidents.
The diameters of the headrest rods and the spacing of the headrest rods from each other vary greatly in different vehicle models. In order for it to be possible for the fastening unit to be used in a wide range of vehicle models, adaptation to different diameters and spacings of the headrest rods therefore has to be possible.
In addition, the attaching and removal of the fastening unit should be able to carried out simply and rapidly without the assistance of tools, even by amateurs.
Various countries have regulations, according to which headrests have to be able to be lowered virtually as far as the upper side of the backrests such that only a gap of small height still remains free between the lower side of the headrests and the upper side of the backrests. A fastening unit mounted on the headrest rods has to take said regulation into account and have a correspondingly low overall height.
There is often the need to secure objects carried in vehicles in such a way that they do not slide, tip over or fall off the seat during a journey. This is particularly irksome in the case of shopping bags, which are frequently used to carry a large number of different impact-sensitive foodstuffs. However, a large number of relatively small objects are also often carried around in handbags, and these can fly around and get damaged in the process or get lost under the seats if the bag tips over in the vehicle. Notebook computers in bags are also often carried in the vehicle, and these can be thrown around in the vehicle in the case of sudden driving maneuvers, possibly sustaining damage in the process or injuring passengers.
On journeys, clothes on one or more clothes hangers, often packed in garment bags, are also placed on the passenger seats or rear seats, and these can slide off the seat and fall on the floor even during slight acceleration, owing to the slippery material, and therefore the clothes can get dirty and crumpled. For this reason, clothes on clothes hangers and in garment bags are often also hung up on the grab handles arranged over the doors at the sides, but here they can obstruct the driver's view in a dangerous manner and hinder access to the rear seats.
On shorter journeys, a jacket is also often hung up on a coat peg, customary in vehicles, which is likewise arranged over the door and is often combined with the grab handle, and this can likewise lead to impairment of the drivers view and hinder entry and exit.
In order to be able to secure even relatively large loads and in order not to put passengers at risk, the device has to be very stable and as compact as possible, and also has to be able to be mounted and removed quickly.